(a) Field of the Invention
The present invention relates to a method of generating oxygen for emergency use wherein an addition compound of sodium carbonate and hydrogen peroxide (2Na.sub.2 CO.sub.3.3H.sub.2 O.sub.2) is employed.
(b) Description of the Prior Art
One's life is sometimes endangered by oxygen starvation at the time of escape from a fire. In such a case, a supply of oxygen is needed. Besides, when poisonous gases are generated at the time of fire, it is necessary to wear a poisonous gas-adsorbing mask which contains active carbon. Thus, it is possible to escape danger. For this particular purpose, it is desired to have an oxygen-generating means which is light in weight and handy to carry around and which can produce oxygen by a simple operation. A handy oxygen-generating means is demanded also in a case in which oxygen inhalation is urgently needed when a person gets sick suddenly.
As an oxygen-generating method applicable to such oxygen-generating means, a method may be considered wherein an addition compound of sodium carbonate and hydrogen peroxide is intermixed with water in the presence of a catalyst so as to generate oxygen. When 2 mols of the addition compound of sodium carbonate and hydrogen peroxide is intermixed with water in the presence of a catalyst, 48 g of oxygen is generated through a chemical reaction as shown by the following chemical reaction formula: EQU 2Na.sub.2 CO.sub.3.3H.sub.2 O.sub.2 .fwdarw.2(Na.sub.2 CO.sub.3.H.sub.2 O)+H.sub.2 O+1.50.sub.2
This reaction takes place as follows. When the addition compound of sodium carbonate and hydrogen peroxide is intermixed with water, the addition compound is decomposed into sodium carbonate and a hydrogen peroxide solution. The hydrogen peroxide solution is then decomposed by the catalyst into water and oxygen. This reaction takes place drastically and, moreover, causes generation of heat. Consequently, depending on the amounts of water and catalyst used, the temperature instantaneously jumps to 100.degree. C. causing bumping. Oxygen and vapor are released simultaneously, and the reaction is completed in a very short space of time. This is not desirable for an oxygen supplying method for cases of accident and sudden illness in which a supply of oxygen is demanded continuously at a constant rate for a certain period of time.
Therefore, in order to generate oxygen in an amount needed for emergency inhalation constantly for a predetermined length of time from an addition compound of sodium carbonate and hydrogen peroxide of an amount that is conveniently carried around and usable in emergencies.
It is necessary to check the drastic generation of oxygen and control the reaction so that oxygen is generated at a constant rate for a predetermined period of time. For this particular purpose, it is necessary to add water and a catalyst to the addition compound of sodium carbonate and hydrogen peroxide little by little and slowly by controlling the amounts of water and catalyst to be added while observing the amount of oxygen being generated. In case of emergency, however, it is practically impossible to get a supply of oxygen by making the above-mentioned control.
As a method of generating oxygen contrived in order to eliminate the above-mentioned disadvantage, it is known to form a catalyst into a plural number of solid bodies each with a different dissolving speed and to add water to a mixture of said solid bodies of the catalyst and addition compound of sodium carbonate and hydrogen peroxide so that the afore-mentioned chemical reaction is thereby caused and oxygen is generated. In said known method of generating oxygen, the solid bodies each with a different dissolving speed is prepared by binding the catalyst with gum arabic solutions or polyvinyl alcohol solutions each with a different concentration, and water is added to a mixture of said solid bodies and addition compound of sodium carbonate and hydrogen peroxide so that oxygen is thereby generated at a constant rate for a long period of time.
By said known method of generating oxygen, it is possible to get a supply of oxygen stably at a constant rate for a certain period of time. However, said known method of generating oxygen has a disadvantage that it is impossible to vary the amount of oxygen to be generated at a time. Besides, said known method of generating oxygen has a disadvantage that, when once used, it is impossible to use the aqueous solution of the addition compound of sodium carbonate and hydrogen peroxide, catalyst, etc. again.